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Date: Thu, 15 Mar 2007 12:18:40 -0700
From: Jeremy Fitzhardinge <jeremy@goop.org>
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To: Dan Hecht <dhecht@vmware.com>
CC: dwalker@mvista.com, cpufreq@lists.linux.org.uk,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       Con Kolivas <kernel@kolivas.org>, Chris Wright <chrisw@sous-sol.org>,
       Virtualization Mailing List <virtualization@lists.osdl.org>,
       john stultz <johnstul@us.ibm.com>, Ingo Molnar <mingo@elte.hu>,
       Thomas Gleixner <tglx@linutronix.de>, paulus@au.ibm.com,
       schwidefsky@de.ibm.com, Rik van Riel <riel@redhat.com>,
       Zachary Amsden <zach@vmware.com>
Subject: Re: Stolen and degraded time and schedulers
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Dan Hecht wrote:
> So, yes, it is per-vcpu.  But, the sched_clock() samples are rebased
> when processes are migrated between runqueues; search sched.c for
> most_recent_timestamp.  It's not perfect since most_recent_timestamp
> between cpu0 and cpu1 do not correspond to the exact same instant, but
> does prevent negative sleep time and is fairly close.

Yes, I noticed that when I looked more carefully, but I wasn't sure
whether it would be sufficient to make it all work out.

    J